Improvement in valves for steam-engines



' JOSEPH W. HOPKINS.

Improvement in Valves for Steam Engines.

PatntedJan.30 ,1872.

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UNITED STATES ATENT FFIGE,

JOSEPH W. HOPKINS, OF NEW YORK, N. Y., ASSIGNOR TO HIMSELF, ALBERT G. BEARUP, AND. PATRICK OARRAHER, JR, OF SAME PLACE.

IMPROVEMENT IN VALVES FOR STEAM-ENGINES.

Specification forming part of Letters Patent No. 123,174, dated January 30, 1872.

To all whom it may concern.-

Be it known that I, JOSEPH W. HOPKINS, of the city, county, and State of New York, have invented a new and useful Improvement in Valves for Steam-Engines; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawing form ing part of this specification, and in which- Figure 1 represents a longitudinal sectional elevation of a valve constructed in accordance with my improvement, and Fig. 2 a transverse vertical section of the same.

Similar letters of reference indicate corresponding parts in both figures.

This invention consists in the combination, within a valve or steam-chest, of an oscillating abutment and a slide-valve with attached cylinder, the abutment being arranged within the cylinder, and being provided with inlets and outlets for operation in concert with passages in the slide-valve and with the ports or passages of the engine-cylinder so that, on turning the abutment at intervals alternately in a reverse direction, steam is admitted to and exhausted from opposite ends alternately of the valve-cylinder to throw the valve. Said improvement is applicable to steam-pumps as well as to steam-engines.

Referring to the accompanying drawing, A represents the valve or steam-chest of an engine, and at its steam-inlet. B is the valveseat, having an exhaust-passage, b, and the usual ports or passages c 0 leading to opposite ends of the engine-cylinder. O is the slidevalve, arranged to work over and controlsaid passages. This valve is of a D-shaped construction, being provided with a central exhaust-cavity, d, and end steam-inlets or passages e 0. Attached to the back of said valve is a cylinder, D, having a steam-inlet, f, in its rear. Within this cylinder is a piston like abutment, E, hung so as to be capable of being turned about its axis and that of the cylinder which it fits by means of a rod, g, but having no motion in direction of the length of the cylinder. Said abutment is provided on its one side, in proximity to the inlet fin valve and connecting with the exhaust-cavity d in the latter.

The operation is as follows: Every time the en ginc-piston approaches the ends of its stroke in opposite directions it communicates, by means of a tappet motion or otherwise, a circular movement in a given direction about its axis to the abutment E, causing one or other passages h h to be brought into communication with the opening f, so as to pass steam to one end of the abutment E and so act upon the cylinder D as to cause the valve 0 to be thrown to the right or to the left, and thus put the ports 0 c in communication, respectively, with the steam -chest A and exhaustpassage 1). During such movement of the valve, and after it has been fairly started, the openin g f passes beyond the passage h or h and shuts off steam. The reverse movement of the valve is effected by turning the abutment E in a reverse direction so as to bring the other one of the passages h or 71/ in communication with the opening f, and one of the exhaust-ports i or i in communication with its exhaust branch is or It, so as to free the one end of the cylinder D of steam and admit it to the opposite, the ports 'i t" operating alternately every throw of the valve. The arrangement is such that as, in the movement of the cylinder D, steam is out 01f from either of the passages h h by the opening f passing beyond them the corresponding exhaust-port t' or i is also cut off from communication with the passages 7t 7t, thereby producing a cushioning action of the cylinder. Means may be provided, if desired, for regulating the period of thus cutting off the steam and exhaust-passages h h and i i, or either.

This constitutes a very simple, quick, and munication between said cylinder, valve-chest oflieient valve. A, and ports or passages in connection with What is here claimed, and desired to be sethe engine-cylinder, substantially as specified.

cured by Letters Patent, is JOSEPH W. HOPKINS.

The combination of the oscillating abutment E with a slide valve, 0, having an at- Witnesses:

tached cylinder, D, surrounding said abnt- FRED. HAYNES,

ment, and ports for passages establishing com- R: E. RABEAU. 

